Quantification of Clarithromycin in Human Plasma by UPLC-MS-MS

A selective, rapid and sensitive ultra performance liquid chromatography tandem mass spectrometry method was developed for the quantitative determination and pharmacokinetic study of clarithromycin in human plasma. The analyte was extracted from human plasma under alkaline condition with diethyl ether. Separation was performed on an ACQUITY UPLC BEH C₁₈ column (50 mm × 2.1 mm i.d., 1.7 μm) with gradient elution at a flow-rate of 0.30 mL min^?1. The mobile phase was 50 mM ammonium acetate (pH 6.8) and acetonitrile. The detection was performed on a triple-quadruple tandem mass spectrometer by multiple reaction monitoring (MRM) mode via electrospray ionization. Linear calibration curves were obtained in the concentration range of 1–3,000 ng mL^?1, with a lower limit of quantification (LLOQ) of 1 ng mL^?1. The intra- and inter-day precision (RSD) values were below 10% and accuracy (RE) ranged from ?7.2 to 6.1% at all QC levels. The method was utilized to support clinical pharmacokinetic study in healthy volunteers following oral administration of clarithromycin extended release tablets.